2007-10-08 Stefan Siegl <stesie@brokenpipe.de>

	Import a number of files from Linux 2.2.14.  Renamed some of them,
	to have unique filenames as required by the make system.

	* linux-src/net/ipv6/addrconf.c: Import file.
	* linux-src/net/ipv6/af_inet6.c: Likewise.
	* linux-src/net/ipv6/exthdrs.c: Likewise.
	* linux-src/net/ipv6/ip6_fib.c: Likewise.
	* linux-src/net/ipv6/ip6_flowlabel.c: Likewise.
	* linux-src/net/ipv6/ip6_input.c: Likewise.
	* linux-src/net/ipv6/ip6_output.c: Likewise.
	* linux-src/net/ipv6/ipv6_sockglue.c: Likewise.
	* linux-src/net/ipv6/mcast.c: Likewise.
	* linux-src/net/ipv6/ndisc.c: Likewise.
	* linux-src/net/ipv6/reassembly.c: Likewise.
	* linux-src/net/ipv6/tcp_ipv6.c: Likewise.
	* linux-src/net/ipv6/datagram_ipv6.c: Import file (was datagram.c).
	* linux-src/net/ipv6/icmpv6.c: Import file (was icmp.c).
	* linux-src/net/ipv6/protocol_ipv6.c: Import file (was protocol.c).
	* linux-src/net/ipv6/raw_ipv6.c: Import file (was raw.c).
	* linux-src/net/ipv6/route_ipv6.c: Import file (was route.c).
	* linux-src/net/ipv6/udp_ipv6.c: Import file (was udp.c).

1 files changed, 1215 insertions, 0 deletions

diff --git a/pfinet/linux-src/net/ipv6/ndisc.c b/pfinet/linux-src/net/ipv6/ndisc.c
new file mode 100644
index 00000000..bb5e0837
--- /dev/null
+++ b/pfinet/linux-src/net/ipv6/ndisc.c
@@ -0,0 +1,1215 @@
+/*
+ *	Neighbour Discovery for IPv6
+ *	Linux INET6 implementation 
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>	
+ *	Mike Shaver		<shaver@ingenia.com>
+ *
+ *	This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+/*
+ *	Changes:
+ *
+ *	Lars Fenneberg			:	fixed MTU setting on receipt
+ *						of an RA.
+ *
+ *	Janos Farkas			:	kmalloc failure checks
+ *	Alexey Kuznetsov		:	state machine reworked
+ *						and moved to net/core.
+ */
+
+/* Set to 3 to get tracing... */
+#define ND_DEBUG 1
+
+#define ND_PRINTK(x...) printk(KERN_DEBUG x)
+#define ND_NOPRINTK(x...) do { ; } while(0)
+#define ND_PRINTK0 ND_PRINTK
+#define ND_PRINTK1 ND_NOPRINTK
+#define ND_PRINTK2 ND_NOPRINTK
+#if ND_DEBUG >= 1
+#undef ND_PRINTK1
+#define ND_PRINTK1 ND_PRINTK
+#endif
+#if ND_DEBUG >= 2
+#undef ND_PRINTK2
+#define ND_PRINTK2 ND_PRINTK
+#endif
+
+#define __NO_VERSION__
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/sched.h>
+#include <linux/net.h>
+#include <linux/in6.h>
+#include <linux/route.h>
+#include <linux/init.h>
+#ifdef CONFIG_SYSCTL
+#include <linux/sysctl.h>
+#endif
+
+#include <linux/if_arp.h>
+#include <linux/ipv6.h>
+#include <linux/icmpv6.h>
+
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+#include <net/ndisc.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/icmp.h>
+
+#include <net/checksum.h>
+#include <linux/proc_fs.h>
+
+static struct socket *ndisc_socket;
+
+static int ndisc_constructor(struct neighbour *neigh);
+static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
+static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
+static int pndisc_constructor(struct pneigh_entry *n);
+static void pndisc_destructor(struct pneigh_entry *n);
+static void pndisc_redo(struct sk_buff *skb);
+
+static struct neigh_ops ndisc_generic_ops =
+{
+	AF_INET6,
+	NULL,
+	ndisc_solicit,
+	ndisc_error_report,
+	neigh_resolve_output,
+	neigh_connected_output,
+	dev_queue_xmit,
+	dev_queue_xmit
+};
+
+static struct neigh_ops ndisc_hh_ops =
+{
+	AF_INET6,
+	NULL,
+	ndisc_solicit,
+	ndisc_error_report,
+	neigh_resolve_output,
+	neigh_resolve_output,
+	dev_queue_xmit,
+	dev_queue_xmit
+};
+
+
+static struct neigh_ops ndisc_direct_ops =
+{
+	AF_INET6,
+	NULL,
+	NULL,
+	NULL,
+	dev_queue_xmit,
+	dev_queue_xmit,
+	dev_queue_xmit,
+	dev_queue_xmit
+};
+
+struct neigh_table nd_tbl =
+{
+	NULL,
+	AF_INET6,
+	sizeof(struct neighbour) + sizeof(struct in6_addr),
+	sizeof(struct in6_addr),
+	ndisc_constructor,
+	pndisc_constructor,
+	pndisc_destructor,
+	pndisc_redo,
+        { NULL, NULL, &nd_tbl, 0, NULL, NULL,
+		  30*HZ, 1*HZ, 60*HZ, 30*HZ, 5*HZ, 3, 3, 0, 3, 1*HZ, (8*HZ)/10, 64, 0 },
+	30*HZ, 128, 512, 1024,
+};
+
+#define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
+
+static u8 *ndisc_fill_option(u8 *opt, int type, void *data, int data_len)
+{
+	int space = NDISC_OPT_SPACE(data_len);
+
+	opt[0] = type;
+	opt[1] = space>>3;
+	memcpy(opt+2, data, data_len);
+	data_len += 2;
+	opt += data_len;
+	if ((space -= data_len) > 0)
+		memset(opt, 0, space);
+	return opt + space;
+}
+
+int ndisc_mc_map(struct in6_addr *addr, char *buf, struct device *dev, int dir)
+{
+	switch (dev->type) {
+	case ARPHRD_ETHER:
+	case ARPHRD_IEEE802:	/* Not sure. Check it later. --ANK */
+	case ARPHRD_FDDI:
+		ipv6_eth_mc_map(addr, buf);
+		return 0;
+	default:
+		if (dir) {
+			memcpy(buf, dev->broadcast, dev->addr_len);
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static int ndisc_constructor(struct neighbour *neigh)
+{
+	struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key;
+	struct device *dev = neigh->dev;
+	struct inet6_dev *in6_dev = ipv6_get_idev(dev);
+	int addr_type;
+
+	if (in6_dev == NULL)
+		return -EINVAL;
+
+	addr_type = ipv6_addr_type(addr);
+	if (in6_dev->nd_parms)
+		neigh->parms = in6_dev->nd_parms;
+
+	if (addr_type&IPV6_ADDR_MULTICAST)
+		neigh->type = RTN_MULTICAST;
+	else
+		neigh->type = RTN_UNICAST;
+	if (dev->hard_header == NULL) {
+		neigh->nud_state = NUD_NOARP;
+		neigh->ops = &ndisc_direct_ops;
+		neigh->output = neigh->ops->queue_xmit;
+	} else {
+		if (addr_type&IPV6_ADDR_MULTICAST) {
+			neigh->nud_state = NUD_NOARP;
+			ndisc_mc_map(addr, neigh->ha, dev, 1);
+		} else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
+			neigh->nud_state = NUD_NOARP;
+			memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
+			if (dev->flags&IFF_LOOPBACK)
+				neigh->type = RTN_LOCAL;
+		} else if (dev->flags&IFF_POINTOPOINT) {
+			neigh->nud_state = NUD_NOARP;
+			memcpy(neigh->ha, dev->broadcast, dev->addr_len);
+		}
+		if (dev->hard_header_cache)
+			neigh->ops = &ndisc_hh_ops;
+		else
+			neigh->ops = &ndisc_generic_ops;
+		if (neigh->nud_state&NUD_VALID)
+			neigh->output = neigh->ops->connected_output;
+		else
+			neigh->output = neigh->ops->output;
+	}
+
+	return 0;
+}
+
+static int pndisc_constructor(struct pneigh_entry *n)
+{
+	struct in6_addr *addr = (struct in6_addr*)&n->key;
+	struct in6_addr maddr;
+	struct device *dev = n->dev;
+
+	if (dev == NULL || ipv6_get_idev(dev) == NULL)
+		return -EINVAL;
+#ifndef CONFIG_IPV6_NO_PB
+	addrconf_addr_solict_mult_old(addr, &maddr);
+	ipv6_dev_mc_inc(dev, &maddr);
+#endif
+#ifdef CONFIG_IPV6_EUI64
+	addrconf_addr_solict_mult_new(addr, &maddr);
+	ipv6_dev_mc_inc(dev, &maddr);
+#endif
+	return 0;
+}
+
+static void pndisc_destructor(struct pneigh_entry *n)
+{
+	struct in6_addr *addr = (struct in6_addr*)&n->key;
+	struct in6_addr maddr;
+	struct device *dev = n->dev;
+
+	if (dev == NULL || ipv6_get_idev(dev) == NULL)
+		return;
+#ifndef CONFIG_IPV6_NO_PB
+	addrconf_addr_solict_mult_old(addr, &maddr);
+	ipv6_dev_mc_dec(dev, &maddr);
+#endif
+#ifdef CONFIG_IPV6_EUI64
+	addrconf_addr_solict_mult_new(addr, &maddr);
+	ipv6_dev_mc_dec(dev, &maddr);
+#endif
+}
+
+
+
+static int
+ndisc_build_ll_hdr(struct sk_buff *skb, struct device *dev,
+		   struct in6_addr *daddr, struct neighbour *neigh, int len)
+{
+	unsigned char ha[MAX_ADDR_LEN];
+	unsigned char *h_dest = NULL;
+
+	skb_reserve(skb, (dev->hard_header_len + 15) & ~15);
+
+	if (dev->hard_header) {
+		if (ipv6_addr_type(daddr) & IPV6_ADDR_MULTICAST) {
+			ndisc_mc_map(daddr, ha, dev, 1);
+			h_dest = ha;
+		} else if (neigh) {
+			h_dest = neigh->ha;
+		} else {
+			neigh = neigh_lookup(&nd_tbl, daddr, dev);
+			if (neigh) {
+				if (neigh->nud_state&NUD_VALID) {
+					memcpy(ha, neigh->ha, dev->addr_len);
+					h_dest = ha;
+				}
+				neigh_release(neigh);
+			}
+		}
+
+		if (dev->hard_header(skb, dev, ETH_P_IPV6, h_dest, NULL, len) < 0)
+			return 0;
+	}
+
+	return 1;
+}
+
+
+/*
+ *	Send a Neighbour Advertisement
+ */
+
+void ndisc_send_na(struct device *dev, struct neighbour *neigh,
+		   struct in6_addr *daddr, struct in6_addr *solicited_addr,
+		   int router, int solicited, int override, int inc_opt) 
+{
+        struct sock *sk = ndisc_socket->sk;
+        struct nd_msg *msg;
+        int len;
+        struct sk_buff *skb;
+	int err;
+
+	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
+
+	if (inc_opt) {
+		if (dev->addr_len)
+			len += NDISC_OPT_SPACE(dev->addr_len);
+		else
+			inc_opt = 0;
+	}
+
+	skb = sock_alloc_send_skb(sk, MAX_HEADER + len + dev->hard_header_len + 15,
+				  0, 0, &err);
+
+	if (skb == NULL) {
+		ND_PRINTK1("send_na: alloc skb failed\n");
+		return;
+	}
+
+	if (ndisc_build_ll_hdr(skb, dev, daddr, neigh, len) == 0) {
+		kfree_skb(skb);
+		return;
+	}
+
+	ip6_nd_hdr(sk, skb, dev, solicited_addr, daddr, IPPROTO_ICMPV6, len);
+
+	msg = (struct nd_msg *) skb_put(skb, len);
+
+        msg->icmph.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
+        msg->icmph.icmp6_code = 0;
+        msg->icmph.icmp6_cksum = 0;
+
+        msg->icmph.icmp6_unused = 0;
+        msg->icmph.icmp6_router    = router;
+        msg->icmph.icmp6_solicited = solicited;
+        msg->icmph.icmp6_override  = !!override;
+
+        /* Set the target address. */
+	ipv6_addr_copy(&msg->target, solicited_addr);
+
+	if (inc_opt)
+		ndisc_fill_option((void*)&msg->opt, ND_OPT_TARGET_LL_ADDR, dev->dev_addr, dev->addr_len);
+
+	/* checksum */
+	msg->icmph.icmp6_cksum = csum_ipv6_magic(solicited_addr, daddr, len, 
+						 IPPROTO_ICMPV6,
+						 csum_partial((__u8 *) msg, 
+							      len, 0));
+
+	dev_queue_xmit(skb);
+
+	icmpv6_statistics.Icmp6OutNeighborAdvertisements++;
+	icmpv6_statistics.Icmp6OutMsgs++;
+}        
+
+void ndisc_send_ns(struct device *dev, struct neighbour *neigh,
+		   struct in6_addr *solicit,
+		   struct in6_addr *daddr, struct in6_addr *saddr) 
+{
+        struct sock *sk = ndisc_socket->sk;
+        struct sk_buff *skb;
+        struct nd_msg *msg;
+        int len;
+	int err;
+
+	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
+	if (dev->addr_len)
+		len += NDISC_OPT_SPACE(dev->addr_len);
+
+	skb = sock_alloc_send_skb(sk, MAX_HEADER + len + dev->hard_header_len + 15,
+				  0, 0, &err);
+	if (skb == NULL) {
+		ND_PRINTK1("send_ns: alloc skb failed\n");
+		return;
+	}
+
+	if (saddr == NULL) {
+		struct inet6_ifaddr *ifa;
+
+		/* use link local address */
+		ifa = ipv6_get_lladdr(dev);
+
+		if (ifa)
+			saddr = &ifa->addr;
+	}
+
+	if (ndisc_build_ll_hdr(skb, dev, daddr, neigh, len) == 0) {
+		kfree_skb(skb);
+		return;
+	}
+
+	ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
+
+	msg = (struct nd_msg *)skb_put(skb, len);
+	msg->icmph.icmp6_type = NDISC_NEIGHBOUR_SOLICITATION;
+	msg->icmph.icmp6_code = 0;
+	msg->icmph.icmp6_cksum = 0;
+	msg->icmph.icmp6_unused = 0;
+
+	/* Set the target address. */
+	ipv6_addr_copy(&msg->target, solicit);
+
+	if (dev->addr_len)
+		ndisc_fill_option((void*)&msg->opt, ND_OPT_SOURCE_LL_ADDR, dev->dev_addr, dev->addr_len);
+
+	/* checksum */
+	msg->icmph.icmp6_cksum = csum_ipv6_magic(&skb->nh.ipv6h->saddr,
+						 daddr, len, 
+						 IPPROTO_ICMPV6,
+						 csum_partial((__u8 *) msg, 
+							      len, 0));
+	/* send it! */
+	dev_queue_xmit(skb);
+
+	icmpv6_statistics.Icmp6OutNeighborSolicits++;
+	icmpv6_statistics.Icmp6OutMsgs++;
+}
+
+void ndisc_send_rs(struct device *dev, struct in6_addr *saddr,
+		   struct in6_addr *daddr)
+{
+	struct sock *sk = ndisc_socket->sk;
+        struct sk_buff *skb;
+        struct icmp6hdr *hdr;
+	__u8 * opt;
+        int len;
+	int err;
+
+	len = sizeof(struct icmp6hdr);
+	if (dev->addr_len)
+		len += NDISC_OPT_SPACE(dev->addr_len);
+
+        skb = sock_alloc_send_skb(sk, MAX_HEADER + len + dev->hard_header_len + 15,
+				  0, 0, &err);
+	if (skb == NULL) {
+		ND_PRINTK1("send_ns: alloc skb failed\n");
+		return;
+	}
+
+	if (ndisc_build_ll_hdr(skb, dev, daddr, NULL, len) == 0) {
+		kfree_skb(skb);
+		return;
+	}
+
+	ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
+
+        hdr = (struct icmp6hdr *) skb_put(skb, len);
+        hdr->icmp6_type = NDISC_ROUTER_SOLICITATION;
+        hdr->icmp6_code = 0;
+        hdr->icmp6_cksum = 0;
+        hdr->icmp6_unused = 0;
+
+	opt = (u8*) (hdr + 1);
+
+	if (dev->addr_len)
+		ndisc_fill_option(opt, ND_OPT_SOURCE_LL_ADDR, dev->dev_addr, dev->addr_len);
+
+	/* checksum */
+	hdr->icmp6_cksum = csum_ipv6_magic(&skb->nh.ipv6h->saddr, daddr, len,
+					   IPPROTO_ICMPV6,
+					   csum_partial((__u8 *) hdr, len, 0));
+
+	/* send it! */
+	dev_queue_xmit(skb);
+
+	icmpv6_statistics.Icmp6OutRouterSolicits++;
+	icmpv6_statistics.Icmp6OutMsgs++;
+}
+		   
+
+static u8 * ndisc_find_option(u8 *opt, int opt_len, int len, int option)
+{
+	while (opt_len <= len) {
+		int l = opt[1]<<3;
+
+		if (opt[0] == option && l >= opt_len)
+			return opt + 2;
+
+		if (l == 0) {
+			if (net_ratelimit())
+			    printk(KERN_WARNING "ndisc: option has 0 len\n");
+			return NULL;
+		}
+
+		opt += l;
+		len -= l;
+	}
+	return NULL;
+}
+
+
+static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
+{
+	/*
+	 *	"The sender MUST return an ICMP
+	 *	 destination unreachable"
+	 */
+	dst_link_failure(skb);
+	kfree_skb(skb);
+}
+
+static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
+{
+	struct in6_addr *saddr = NULL;
+	struct in6_addr mcaddr;
+	struct device *dev = neigh->dev;
+	struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
+	int probes = neigh->probes;
+
+	if (skb && ipv6_chk_addr(&skb->nh.ipv6h->saddr, dev, 0))
+		saddr = &skb->nh.ipv6h->saddr;
+
+	if ((probes -= neigh->parms->ucast_probes) < 0) {
+		if (!(neigh->nud_state&NUD_VALID))
+			ND_PRINTK1("trying to ucast probe in NUD_INVALID\n");
+		ndisc_send_ns(dev, neigh, target, target, saddr);
+	} else if ((probes -= neigh->parms->app_probes) < 0) {
+#ifdef CONFIG_ARPD
+		neigh_app_ns(neigh);
+#endif
+	} else {
+#ifdef CONFIG_IPV6_EUI64
+		addrconf_addr_solict_mult_new(target, &mcaddr);
+		ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
+#endif
+#ifndef CONFIG_IPV6_NO_PB
+		addrconf_addr_solict_mult_old(target, &mcaddr);
+		ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
+#endif
+	}
+}
+
+
+static void ndisc_update(struct neighbour *neigh, u8* opt, int len, int type)
+{
+	opt = ndisc_find_option(opt, neigh->dev->addr_len+2, len, type);
+	neigh_update(neigh, opt, NUD_STALE, 1, 1);
+}
+
+static void ndisc_router_discovery(struct sk_buff *skb)
+{
+        struct ra_msg *ra_msg = (struct ra_msg *) skb->h.raw;
+	struct neighbour *neigh;
+	struct inet6_dev *in6_dev;
+	struct rt6_info *rt;
+	int lifetime;
+	int optlen;
+
+	__u8 * opt = (__u8 *)(ra_msg + 1);
+
+	optlen = (skb->tail - skb->h.raw) - sizeof(struct ra_msg);
+
+	if (skb->nh.ipv6h->hop_limit != 255) {
+		printk(KERN_INFO
+		       "NDISC: fake router advertisment received\n");
+		return;
+	}
+
+	/*
+	 *	set the RA_RECV flag in the interface
+	 */
+
+	in6_dev = ipv6_get_idev(skb->dev);
+	if (in6_dev == NULL) {
+		ND_PRINTK1("RA: can't find in6 device\n");
+		return;
+	}
+	if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_ra)
+		return;
+
+	if (in6_dev->if_flags & IF_RS_SENT) {
+		/*
+		 *	flag that an RA was received after an RS was sent
+		 *	out on this interface.
+		 */
+		in6_dev->if_flags |= IF_RA_RCVD;
+	}
+
+	lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
+
+	rt = rt6_get_dflt_router(&skb->nh.ipv6h->saddr, skb->dev);
+
+	if (rt && lifetime == 0) {
+		ip6_del_rt(rt);
+		dst_release(&rt->u.dst);
+		rt = NULL;
+	}
+
+	if (rt == NULL && lifetime) {
+		ND_PRINTK2("ndisc_rdisc: adding default router\n");
+
+		rt = rt6_add_dflt_router(&skb->nh.ipv6h->saddr, skb->dev);
+		if (rt == NULL) {
+			ND_PRINTK1("route_add failed\n");
+			return;
+		}
+
+		neigh = rt->rt6i_nexthop;
+		if (neigh == NULL) {
+			ND_PRINTK1("nd: add default router: null neighbour\n");
+			dst_release(&rt->u.dst);
+			return;
+		}
+		neigh->flags |= NTF_ROUTER;
+
+		/*
+		 *	If we where using an "all destinations on link" route
+		 *	delete it
+		 */
+
+		rt6_purge_dflt_routers(RTF_ALLONLINK);
+	}
+
+	if (rt)
+		rt->rt6i_expires = jiffies + (HZ * lifetime);
+
+	if (ra_msg->icmph.icmp6_hop_limit)
+		in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
+
+	/*
+	 *	Update Reachable Time and Retrans Timer
+	 */
+
+	if (in6_dev->nd_parms) {
+		if (ra_msg->retrans_timer)
+			in6_dev->nd_parms->retrans_time = (ntohl(ra_msg->retrans_timer)*HZ)/1000;
+
+		if (ra_msg->reachable_time) {
+			__u32 rtime = (ntohl(ra_msg->reachable_time)*HZ)/1000;
+
+			if (rtime != in6_dev->nd_parms->base_reachable_time) {
+				in6_dev->nd_parms->base_reachable_time = rtime;
+				in6_dev->nd_parms->gc_staletime = 3 * rtime;
+				in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
+			}
+		}
+	}
+
+	/*
+	 *	Process options.
+	 */
+
+        while (optlen > 0) {
+                int len = (opt[1] << 3);
+
+		if (len == 0) {
+			ND_PRINTK0("RA: opt has 0 len\n");
+			break;
+		}
+
+                switch(*opt) {
+                case ND_OPT_SOURCE_LL_ADDR:
+
+			if (rt == NULL)
+				break;
+			
+			if ((neigh = rt->rt6i_nexthop) != NULL &&
+			    skb->dev->addr_len + 2 >= len)
+				neigh_update(neigh, opt+2, NUD_STALE, 1, 1);
+			break;
+
+                case ND_OPT_PREFIX_INFO:
+			addrconf_prefix_rcv(skb->dev, opt, len);
+                        break;
+
+                case ND_OPT_MTU:
+			{
+				int mtu;
+				
+				mtu = htonl(*(__u32 *)(opt+4));
+
+				if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
+					ND_PRINTK0("NDISC: router "
+						   "announcement with mtu = %d\n",
+						   mtu);
+					break;
+				}
+
+				if (in6_dev->cnf.mtu6 != mtu) {
+					in6_dev->cnf.mtu6 = mtu;
+
+					if (rt)
+						rt->u.dst.pmtu = mtu;
+
+					rt6_mtu_change(skb->dev, mtu);
+				}
+			}
+                        break;
+
+		case ND_OPT_TARGET_LL_ADDR:
+		case ND_OPT_REDIRECT_HDR:
+			ND_PRINTK0("got illegal option with RA");
+			break;
+		default:
+			ND_PRINTK0("unkown option in RA\n");
+                };
+                optlen -= len;
+                opt += len;
+        }
+	if (rt)
+		dst_release(&rt->u.dst);
+}
+
+static void ndisc_redirect_rcv(struct sk_buff *skb)
+{
+	struct inet6_dev *in6_dev;
+	struct icmp6hdr *icmph;
+	struct in6_addr *dest;
+	struct in6_addr *target;	/* new first hop to destination */
+	struct neighbour *neigh;
+	int on_link = 0;
+	int optlen;
+
+	if (skb->nh.ipv6h->hop_limit != 255) {
+		printk(KERN_WARNING "NDISC: fake ICMP redirect received\n");
+		return;
+	}
+
+	if (!(ipv6_addr_type(&skb->nh.ipv6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
+		printk(KERN_WARNING "ICMP redirect: source address is not linklocal\n");
+		return;
+	}
+
+	optlen = skb->tail - skb->h.raw;
+	optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
+
+	if (optlen < 0) {
+		printk(KERN_WARNING "ICMP redirect: packet too small\n");
+		return;
+	}
+
+	icmph = (struct icmp6hdr *) skb->h.raw;
+	target = (struct in6_addr *) (icmph + 1);
+	dest = target + 1;
+
+	if (ipv6_addr_type(dest) & IPV6_ADDR_MULTICAST) {
+		printk(KERN_WARNING "ICMP redirect for multicast addr\n");
+		return;
+	}
+
+	if (ipv6_addr_cmp(dest, target) == 0) {
+		on_link = 1;
+	} else if (!(ipv6_addr_type(target) & IPV6_ADDR_LINKLOCAL)) {
+		printk(KERN_WARNING "ICMP redirect: target address is not linklocal\n");
+		return;
+	}
+
+	in6_dev = ipv6_get_idev(skb->dev);
+	if (!in6_dev || in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
+		return;
+
+	/* passed validation tests */
+
+	/*
+	   We install redirect only if nexthop state is valid.
+	 */
+
+	neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
+	if (neigh) {
+		ndisc_update(neigh, (u8*)(dest + 1), optlen, ND_OPT_TARGET_LL_ADDR);
+		if (neigh->nud_state&NUD_VALID)
+			rt6_redirect(dest, &skb->nh.ipv6h->saddr, neigh, on_link);
+		else
+			__neigh_event_send(neigh, NULL);
+		neigh_release(neigh);
+	}
+}
+
+void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
+			 struct in6_addr *target)
+{
+	struct sock *sk = ndisc_socket->sk;
+	int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
+	struct sk_buff *buff;
+	struct inet6_ifaddr *ifp;
+	struct icmp6hdr *icmph;
+	struct in6_addr *addrp;
+	struct device *dev;
+	struct rt6_info *rt;
+	u8 *opt;
+	int rd_len;
+	int err;
+	int hlen;
+
+	dev = skb->dev;
+	rt = rt6_lookup(&skb->nh.ipv6h->saddr, NULL, dev->ifindex, 1);
+
+	if (rt == NULL)
+		return;
+
+	if (rt->rt6i_flags & RTF_GATEWAY) {
+		ND_PRINTK1("ndisc_send_redirect: not a neighbour\n");
+		dst_release(&rt->u.dst);
+		return;
+	}
+	if (!xrlim_allow(&rt->u.dst, 1*HZ)) {
+		dst_release(&rt->u.dst);
+		return;
+	}
+	dst_release(&rt->u.dst);
+
+	if (dev->addr_len) {
+		if (neigh->nud_state&NUD_VALID) {
+			len  += NDISC_OPT_SPACE(dev->addr_len);
+		} else {
+			/* If nexthop is not valid, do not redirect!
+			   We will make it later, when will be sure,
+			   that it is alive.
+			 */
+			return;
+		}
+	}
+
+	rd_len = min(IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
+	rd_len &= ~0x7;
+	len += rd_len;
+
+	ifp = ipv6_get_lladdr(dev);
+
+	if (ifp == NULL) {
+		ND_PRINTK1("redirect: no link_local addr for dev\n");
+		return;
+	}
+
+	buff = sock_alloc_send_skb(sk, MAX_HEADER + len + dev->hard_header_len + 15,
+				   0, 0, &err);
+	if (buff == NULL) {
+		ND_PRINTK1("ndisc_send_redirect: alloc_skb failed\n");
+		return;
+	}
+
+	hlen = 0;
+
+	if (ndisc_build_ll_hdr(buff, dev, &skb->nh.ipv6h->saddr, NULL, len) == 0) {
+		kfree_skb(buff);
+		return;
+	}
+
+	ip6_nd_hdr(sk, buff, dev, &ifp->addr, &skb->nh.ipv6h->saddr,
+		   IPPROTO_ICMPV6, len);
+
+	icmph = (struct icmp6hdr *) skb_put(buff, len);
+
+	memset(icmph, 0, sizeof(struct icmp6hdr));
+	icmph->icmp6_type = NDISC_REDIRECT;
+
+	/*
+	 *	copy target and destination addresses
+	 */
+
+	addrp = (struct in6_addr *)(icmph + 1);
+	ipv6_addr_copy(addrp, target);
+	addrp++;
+	ipv6_addr_copy(addrp, &skb->nh.ipv6h->daddr);
+
+	opt = (u8*) (addrp + 1);
+
+	/*
+	 *	include target_address option
+	 */
+
+	if (dev->addr_len)
+		opt = ndisc_fill_option(opt, ND_OPT_TARGET_LL_ADDR, neigh->ha, dev->addr_len);
+
+	/*
+	 *	build redirect option and copy skb over to the new packet.
+	 */
+
+	memset(opt, 0, 8);	
+	*(opt++) = ND_OPT_REDIRECT_HDR;
+	*(opt++) = (rd_len >> 3);
+	opt += 6;
+
+	memcpy(opt, skb->nh.ipv6h, rd_len - 8);
+
+	icmph->icmp6_cksum = csum_ipv6_magic(&ifp->addr, &skb->nh.ipv6h->saddr,
+					     len, IPPROTO_ICMPV6,
+					     csum_partial((u8 *) icmph, len, 0));
+
+	dev_queue_xmit(buff);
+
+	icmpv6_statistics.Icmp6OutRedirects++;
+	icmpv6_statistics.Icmp6OutMsgs++;
+}
+
+static __inline__ struct neighbour *
+ndisc_recv_ns(struct in6_addr *saddr, struct sk_buff *skb)
+{
+	u8 *opt;
+
+	opt = skb->h.raw;
+	opt += sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
+	opt = ndisc_find_option(opt, skb->dev->addr_len+2, skb->tail - opt, ND_OPT_SOURCE_LL_ADDR);
+
+	return neigh_event_ns(&nd_tbl, opt, saddr, skb->dev);
+}
+
+static __inline__ int ndisc_recv_na(struct neighbour *neigh, struct sk_buff *skb)
+{
+	struct nd_msg *msg = (struct nd_msg *) skb->h.raw;
+	u8 *opt;
+
+	opt = skb->h.raw;
+	opt += sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
+	opt = ndisc_find_option(opt, skb->dev->addr_len+2, skb->tail - opt, ND_OPT_TARGET_LL_ADDR);
+
+	return neigh_update(neigh, opt,
+			    msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
+			    msg->icmph.icmp6_override, 1);
+}
+
+static void pndisc_redo(struct sk_buff *skb)
+{
+	ndisc_rcv(skb, skb->len);
+	kfree_skb(skb);
+}
+
+int ndisc_rcv(struct sk_buff *skb, unsigned long len)
+{
+	struct device *dev = skb->dev;
+	struct in6_addr *saddr = &skb->nh.ipv6h->saddr;
+	struct in6_addr *daddr = &skb->nh.ipv6h->daddr;
+	struct nd_msg *msg = (struct nd_msg *) skb->h.raw;
+	struct neighbour *neigh;
+	struct inet6_ifaddr *ifp;
+
+	switch (msg->icmph.icmp6_type) {
+	case NDISC_NEIGHBOUR_SOLICITATION:
+		if ((ifp = ipv6_chk_addr(&msg->target, dev, 1)) != NULL) {
+			int addr_type = ipv6_addr_type(saddr);
+
+			if (ifp->flags & ADDR_INVALID)
+				return 0;
+			if (ifp->flags & DAD_INCOMPLETE) {
+				/* Address is tentative. If the source
+				   is unspecified address, it is someone
+				   does DAD, otherwise we ignore solicitations
+				   until DAD timer expires.
+				 */
+				if (addr_type == IPV6_ADDR_ANY)
+					addrconf_dad_failure(ifp);
+				return 0;
+			}
+
+			if (addr_type == IPV6_ADDR_ANY) {
+				struct in6_addr maddr;
+
+				ipv6_addr_all_nodes(&maddr);
+				ndisc_send_na(dev, NULL, &maddr, &ifp->addr, 
+					      ifp->idev->cnf.forwarding, 0, 1, 1);
+				return 0;
+			}
+
+			if (addr_type & IPV6_ADDR_UNICAST) {
+				int inc = ipv6_addr_type(daddr)&IPV6_ADDR_MULTICAST;
+
+				if (inc)
+					nd_tbl.stats.rcv_probes_mcast++;
+				else
+					nd_tbl.stats.rcv_probes_ucast++;
+
+				/* 
+				 *	update / create cache entry
+				 *	for the source adddress
+				 */
+
+				neigh = ndisc_recv_ns(saddr, skb);
+
+				if (neigh) {
+					ndisc_send_na(dev, neigh, saddr, &ifp->addr, 
+						      ifp->idev->cnf.forwarding, 1, inc, inc);
+					neigh_release(neigh);
+				}
+			}
+		} else {
+			struct inet6_dev *in6_dev = ipv6_get_idev(dev);
+			int addr_type = ipv6_addr_type(saddr);
+
+			if (in6_dev && in6_dev->cnf.forwarding &&
+			    (addr_type & IPV6_ADDR_UNICAST) &&
+			    pneigh_lookup(&nd_tbl, &msg->target, dev, 0)) {
+				int inc = ipv6_addr_type(daddr)&IPV6_ADDR_MULTICAST;
+
+				if (skb->stamp.tv_sec == 0 ||
+				    skb->pkt_type == PACKET_HOST ||
+				    inc == 0 ||
+				    in6_dev->nd_parms->proxy_delay == 0) {
+					if (inc)
+						nd_tbl.stats.rcv_probes_mcast++;
+					else
+						nd_tbl.stats.rcv_probes_ucast++;
+
+					neigh = ndisc_recv_ns(saddr, skb);
+
+					if (neigh) {
+						ndisc_send_na(dev, neigh, saddr, &msg->target,
+							      0, 1, 0, inc);
+						neigh_release(neigh);
+					}
+				} else {
+					/* Hack. It will be freed upon exit from
+					   ndisc_rcv
+					 */
+					atomic_inc(&skb->users);
+					pneigh_enqueue(&nd_tbl, in6_dev->nd_parms, skb);
+					return 0;
+				}
+			}
+		}
+		return 0;
+
+	case NDISC_NEIGHBOUR_ADVERTISEMENT:
+		if ((ipv6_addr_type(saddr)&IPV6_ADDR_MULTICAST) &&
+		    msg->icmph.icmp6_solicited) {
+			ND_PRINTK0("NDISC: solicited NA is multicasted\n");
+			return 0;
+		}
+		/* BUG! Target can be link-local on ANOTHER interface. Fixed. */
+		if ((ifp = ipv6_chk_addr(&msg->target, dev, 1))) {
+			if (ifp->flags & ADDR_INVALID)
+				return 0;
+			if (ifp->flags & DAD_INCOMPLETE) {
+				addrconf_dad_failure(ifp);
+				return 0;
+			}
+			/* What should we make now? The advertisement
+			   is invalid, but ndisc specs say nothing
+			   about it. It could be misconfiguration, or
+			   an smart proxy agent tries to help us :-)
+			 */
+			ND_PRINTK0("%s: someone avertise our address!\n",
+				   ifp->idev->dev->name);
+			return 0;
+		}
+		neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 0);
+
+		if (neigh) {
+			if (neigh->flags & NTF_ROUTER) {
+				if (msg->icmph.icmp6_router == 0) {
+					/*
+					 *	Change: router to host
+					 */
+					struct rt6_info *rt;
+					rt = rt6_get_dflt_router(saddr, skb->dev);
+					if (rt) {
+						/* It is safe only because
+						   we aer in BH */
+						dst_release(&rt->u.dst);
+						ip6_del_rt(rt);
+					}
+				}
+			} else {
+				if (msg->icmph.icmp6_router)
+					neigh->flags |= NTF_ROUTER;
+			}
+
+			ndisc_recv_na(neigh, skb);
+			neigh_release(neigh);
+		}
+		break;
+
+	case NDISC_ROUTER_ADVERTISEMENT:
+		ndisc_router_discovery(skb);
+		break;
+
+	case NDISC_REDIRECT:
+		ndisc_redirect_rcv(skb);
+		break;
+	};
+
+	return 0;
+}
+
+#ifdef CONFIG_PROC_FS
+#ifndef CONFIG_RTNETLINK
+int ndisc_get_info(char *buffer, char **start, off_t offset, int length, int dummy)
+{
+	int len=0;
+	off_t pos=0;
+	int size;
+	unsigned long now = jiffies;
+	int i;
+
+	neigh_table_lock(&nd_tbl);
+
+	for (i = 0; i <= NEIGH_HASHMASK; i++) {
+		struct neighbour *neigh;
+
+		for (neigh = nd_tbl.hash_buckets[i]; neigh; neigh = neigh->next) {
+			int j;
+
+			size = 0;
+			for (j=0; j<16; j++) {
+				sprintf(buffer+len+size, "%02x", neigh->primary_key[j]);
+				size += 2;
+			}
+
+			size += sprintf(buffer+len+size,
+				       " %02x %02x %02x %02x %08lx %08lx %08x %04x %04x %04x %8s ", i,
+				       128,
+				       neigh->type,
+				       neigh->nud_state,
+				       now - neigh->used,
+				       now - neigh->confirmed,
+				       neigh->parms->reachable_time,
+				       neigh->parms->gc_staletime,
+				       atomic_read(&neigh->refcnt),
+				       neigh->flags | (!neigh->hh ? 0 : (neigh->hh->hh_output==dev_queue_xmit ? 4 : 2)),
+				       neigh->dev->name);
+
+			if ((neigh->nud_state&NUD_VALID) && neigh->dev->addr_len) {
+				for (j=0; j < neigh->dev->addr_len; j++) {
+					sprintf(buffer+len+size, "%02x", neigh->ha[j]);
+					size += 2;
+				}
+			} else {
+                                size += sprintf(buffer+len+size, "000000000000");
+			}
+			size += sprintf(buffer+len+size, "\n");
+			len += size;
+			pos += size;
+		  
+			if (pos <= offset)
+				len=0;
+			if (pos >= offset+length)
+				goto done;
+		}
+	}
+
+done:
+	neigh_table_unlock(&nd_tbl);
+
+	*start = buffer+len-(pos-offset);	/* Start of wanted data */
+	len = pos-offset;			/* Start slop */
+	if (len>length)
+		len = length;			/* Ending slop */
+	if (len<0)
+		len = 0;
+	return len;
+}
+
+struct proc_dir_entry ndisc_proc_entry =
+{
+        PROC_NET_NDISC, 5, "ndisc",
+        S_IFREG | S_IRUGO, 1, 0, 0,
+        0, NULL,
+        &ndisc_get_info
+};
+#endif
+#endif	/* CONFIG_PROC_FS */
+
+
+
+__initfunc(int ndisc_init(struct net_proto_family *ops))
+{
+	struct sock *sk;
+        int err;
+
+	ndisc_socket = sock_alloc();
+	if (ndisc_socket == NULL) {
+		printk(KERN_ERR
+		       "Failed to create the NDISC control socket.\n");
+		return -1;
+	}
+	ndisc_socket->inode->i_uid = 0;
+	ndisc_socket->inode->i_gid = 0;
+	ndisc_socket->type = SOCK_RAW;
+
+	if((err = ops->create(ndisc_socket, IPPROTO_ICMPV6)) < 0) {
+		printk(KERN_DEBUG 
+		       "Failed to initializee the NDISC control socket (err %d).\n",
+		       err);
+		sock_release(ndisc_socket);
+		ndisc_socket = NULL; /* For safety. */
+		return err;
+	}
+
+	sk = ndisc_socket->sk;
+	sk->allocation = GFP_ATOMIC;
+	sk->net_pinfo.af_inet6.hop_limit = 255;
+	/* Do not loopback ndisc messages */
+	sk->net_pinfo.af_inet6.mc_loop = 0;
+	sk->num = 256;
+
+        /*
+         * Initialize the neighbour table
+         */
+	
+	neigh_table_init(&nd_tbl);
+
+#ifdef CONFIG_PROC_FS
+#ifndef CONFIG_RTNETLINK
+	proc_net_register(&ndisc_proc_entry);
+#endif
+#endif
+#ifdef CONFIG_SYSCTL
+	neigh_sysctl_register(NULL, &nd_tbl.parms, NET_IPV6, NET_IPV6_NEIGH, "ipv6");
+#endif
+
+	return 0;
+}
+
+void ndisc_cleanup(void)
+{
+#ifdef CONFIG_PROC_FS
+#ifndef CONFIG_RTNETLINK
+        proc_net_unregister(ndisc_proc_entry.low_ino);
+#endif
+#endif
+	neigh_table_clear(&nd_tbl);
+	sock_release(ndisc_socket);
+	ndisc_socket = NULL; /* For safety. */
+}